Hydraulic jack



Nov. 17, 1931.

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Application filed May 14,

This invention relates to a hydraulic lifting means, sometimes referred to as a hydraulic jack and Comprises improvements hereinafter set forth. 2 a V 7 An object of my invention is to provide a lifting jack having a plurality of pumps adapted to be operated simultaneously to operate the lifting mechanism.

Another object of my invention is to provide a lifting jack having outer and inner casing, with a lifting mechanism mounted in the inner casing and with meansfor pumping a fluid from the outer casing into the inner casing to raise the lifting mechanism. Another object of my invention is to provide a lifting jack having two pumps geared together to operate at the same time so that while one pump is exerting alifting' effect the other pump will be drawing fluid from an outer container to force it in the inner container while the other pump is pumping a better illustration;

Figure 2 is a cross-sectional view taken along-the line 2-2 in Figure 1 but showing the pump in reversed position, as shown n Figure 1; I I

Figure 3 is an enlarged detail in crosssection of the upper portion of my lifting 'ack' Q 1 Figure 4 is a cross-sectional view taken along the line 4+4 in Figure 2; V i

Figure 5 is a plan view of the base portlon inner containers'removed therefrom. V

Referring more particularly to the drawings the'numeral 10 indicates the base portionof my jackwhich has the outercylinder member 11 threadably secured therein and also hasthe inner cylinder member 12 threadably secured therein andfinthe inner cylinder member the lifting mechanism 13 is adapted to be mounted, said lifting mechanism having 1929.. serial N5. 363,021.

the member 14 loosely secured thereon with thewasher member 15 which is preferably of leather and the additional washer member '16 is preferably of rubber and these members 14, 15 and 16 are rigidly secured on themem- 65 her 13 by means of the nut 1-7 which isthread ably secured on the'lower end of the member 13. 1 r r The member 10 has the hollowed out portion 18 in which the outer cylinder '11 is threadablysecured, and the ring portion 19 occurs within this portion 18 and on the inner side of this portion 19 the inner cylinder712'is threadably secured. These cylinders at the upper end thereof have the memher 20 which has the outer ring portion21 which is threadably secured to the exterior of the cylinder 11 and the inner ring portion 221s interiorly threaded and is fadaptedto engage the 'inner'cylinder 12. The rod 13 7 is adapted to be slidably mounted in a hole in the center of the member 20 and this mem her 20 has the air vent hole 23 in which the plug 2 1 .is adapted to be secured when the device is not in use or if it is desired to transport the same from place to place, it being evident that the plug 241 will be removed so that the hole 23 may serve as an airvent when the device is adapted to be operated.

The base membrlO has the pipes 25 and 26 threadably mounted therein in a horizontal manner, and these pipes project inwardly and open into the vertically disposed chambers 27 and'28 and in the lower portion of the chambers 27 and 28 the members 29 and 30 are threadably secured, these members 29 and 30 having the balls 31 and 32 loosely secured therein; and are adapted to rest on the seats 33 and 34; respectively, said seats coinciding with the passageways 35 and 36 which project vertically and are connected with the laterally projecting passageways 37 and 38and leading downward from the space between the inner and outer cylinders of the passageways 39 and 40 which coincides with the horizontal passageways 37 and 38 thus forming a passageway for the fluid contained between the outer and inner cylinders to pass downwardly and through T v the valve members 29 and 30 into the charm bers 27 and 28. In the upper portion of these chambers 27 and 28 are mounted the members 42 and 43 which have the balls 45a and 44 mounted therein in seats similar to the seats already described for the members 29 and 30. All of these members 29, 30, 42 and 43 have the wires 45 mounted therein to prevent the escape of the check valve members 31, 32, 44 and 45a.

The pipes 25 and 26 have mounted therein the piston members and 51 and on the inner ends of these piston members are mounted the washer member 52, the rubber gasket 53 and the gasket 54 by means of the nut 55 which secures these members rigidly on the rods 50 and 51 as the case may be, the structure shown in Figure 4 being identical on the rod 51.

These rods 50 and 51 are slidably mounted in the members 57 and 58 which are threadably secured on the ends of the pipe members 25 and L26, and the ends of the rods 50 and 51 have secured thereon the members 58a and 59 and the rod 50 has the hole 60 therein by means of which thepump mechanism may be connected to any prime mover. These members 58a and 59 are connected to each other by means of the rods 61 and 62, said rods being connected tothe members 58a and59 by means of the bolts 63 and 64 which pierce not only the members 61 and 62 but also the members 58a and 59 and the rod members 50 and 51 thus forming a rigid mechanism to cause both pumps to work at the same time. Thus, while the .piston connected to the rod 50 is traveling inward forcing the liquid up by the ball 45a into the inner chamber, the ball 32 will be resting on its seat and at the same time the piston on the rod 5l will be traveling outwardly closing the ball 44 on its seat and drawing liquid from the outer container therethrough the passageway 40, the passageway 33 up by the ball 31 and into the chamber 27.

The passageways 37 and 38 are closed at their outer ends by means of the plugs 7 O and 71, the position of the passageways 39 and 40 :at right angle to the passageways 37 and 38 being made forsake of mechanical design, it being evident that these passageways may be of any shape desired. I p The vertically disposed passageway leads downward from the inside ofthe cylinder 12 and connects with thelateral projecting passageway 7 6 and an elbow member 77 is threadably secured in the outer portion of the passageway 76 and the pipe member 78 is connected to said elbow member and projects upwardly and is threadably connected to the union 7 9 with the pipe 80 projecting upwardly and being threadably connected to valve 81and the pipe 82 leads fromsaid valve to the elbow member 83 which is threadably connected in a hole in the outer casing 11 to communicate with the interior of said casing, the purpose of this arrangement being that when it is desired to allow the lifting mechanism 13 and associated parts to return to lowered position that the valve 81 will be opened and the ram 13 and associated parts will travel downwardly and force the liquid through the passageways 7 5 and 76 and upwardly through the pipes and valve mechanism into the upper portion of the outer compartment which is between the cylinders 11 and 12.

I have shown my hydraulic ack with the upper portion of the rod 13 broken away for the purpose of indicating that this lifting mechanism may be "applied to any desired mechanism, such as to an automobile, dump truck for purposes of dumping the same and it is evident that it can be applied to a various number of'uses, it being capable of being applied to any use where a fluid operating jack is desired.

The base member 10 has the holes 85 and 86 in the side portions thereof, the purpose of these holes being that plugs or other suitable devices may be secured therein for securing the base member to any suitable support.

In the drawings and specification I have set forth a preferred embodiment of my invention, and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposes of limitation, the scope of the invention being set forth in the appended claim.

I claim:

In a hydraulic jack, a base member, an upwardly projecting circular rim portion on top of said base member and being threaded interiorly, an outer cylinder threadably secured at its lower end in said rim, an annular projection on said base located within the rim and being threaded to receive the lower end of an inner cylinder to form a compartment between the two cylinders, said base having two oppositely disposed alined, horizontally disposed pump chambers, a piston slidably mounted in each cylinder,

means connecting the piston for operation in the same direction at'the same time, said base also having two vertically disposed chambers, each chamber communicating at its central portion with one of the pump chambers, a check valve in the lower portion of the vertical chamber, said base have passageways leading from below each check valve to the compartment between the two cylinders, a check valve-in'the top portion of-each of the vertical chambers, the upper ends of said chambers communicating with the interior of the inner cylinder, the check valve permitting the pumps to withdraw .a liquid from the compartment between the cylinders and to force the liquidinto the inner-cylinder, a piston mounted in the inner cylinder, a

shaft connected to the-pistonin the inner cylinder and projecting from the upper end of the inner cylinder, and manually controlled means for permitting flow of fluid from the bottom of the inner cylinder into the top of the outer cylinder when downward pressure is appliedto the piston in the inner cylinder.

In testimony whereof I aflix my signature.

WILLIAM W. SMOAK. 

